Vapor electric device



Dec. 7 1926.

H 1,610,059 c. KRAMER VAPOR ELECTRIC DEVICE Filed June 1925 Inventor":

His Attorney Patente d Dec. 7, 1926.

' v UNITED 11T]:S',

PATENT OFFICE.

cmusrmn KRAMER, or rlmxow, GERMANY, 'assrenon T GENERAL ELEc'raIc icomranr, A oonronmrron on NEW YORK.

. VAPOR ELECTRIC DEVICE.

Application' filed June 20, 1923, Serial No. 646,538, and in GermanyJuly 27, 1922.

The present invention relates to vapor electric devices, particularlymercury arc rectifiers of large power, and it is the object of myinvention to provide-means for preventing deleterious reverse arcing andsimilar disturbances in these devices.

In accordance with my invention I have provided a new form of anode forvapor electric devices. which is provided with a large number ofdistinct projections.

- The accompanying drawing shows in section a rect fier containing ananode embody- 1 ing my invention.

One of the causes of reverse discharges in ';rectifiers that is,discharges having a polarity opposite to the rectifier current, is theconcentration of the discharge at an accidental point or protuberance onthe anode surface, -for example, a fusion globule on -the anode surface.Hereby this part of the 'anode'becomes very highly heated thereby givingrise to reverse arcing. Formerly,

the anode surfaces were carefully rounded,

and in some cases even highly polished and itfijplated with nickel orprecious metal.

.In contrast to this procedure I haveprovJ fl vided the anode withnumerousfdistinct points orv protuberances, to prevent a concentrationof the arc. .One embodiment of my" invention is showni'nithe drawing.The

' l rectifier illustrated comprises as usual a container 1, in whichthere is provided a cathode, 2, and an anode 3. The side branch,

or starting anode 4, has nothing to do with my invention as any suitablestarting means may be used. 1

The anode 3, which may consist of graphite, tungsten, or other suitablematerial, is provided with numerous sharp corners and edges by crossriflling the same as indicated. By this means there are present insteadof an accidental single point or-few points, a multitude of smallprojections or knurls distributed over the surface of the anode so thata dangerous concentration of current at an isolated point is avoided.Experience has shown that the danger of reverse arcingv is materiallyreduced in devices containing the described form of anode.

' What I'claim as new and desire to secure by Letters Patent of theUnited States, is:

1. An anode for electric discharge devices, said anode being providedwith a knurled surface.

- which has a surface provided with cross rifiiing, thereby, producing aplurality of sharp corners. f

In witness whereof, I have hereunto set my hand this 24th day of May,1923. v

T CHRISTIAN KRAMER.

